Air conditioning apparatus



Sept. 26,1939. c. R. DOWNS El AL AIR CONDITIONING APPARATUS Filed May 14, 1935 7 Sheets-Sheet 1 INVENTORS CHA ELL-'5 e. DOWNS JOSEPH JMSP/SEL Sept. 26, 1939.

C. R. DOWNS ET AL AIR CONDITIONING APPARATUS Filed May 14, 1935 7 Sheets-Sheet 2 INVENTORS Sept. 26, 1939. c DOWNS ET AL 2,174,186

AIR CONDITIONING APPARATUS INVENTORS CHARLES E. DOWNS Sept. 26, 1939. c. R. DOWNS El AL AIR CONDITIONING APPARATUS Filed May 14, 1935 7 Sheets-Sheet 4 N INVENTORS 3 CHARLES 2.DOW/V$ Sept. 26, 1939. c. R. DOW NS ET AL AIR CONDITIONING APPARATUS '7 Sheets-Sheet 6 Filed May 14, 1955 INVENTORS CHARLES E. DOWNS JOSEPH IMSP/SEL AN Sept. 26, 1939. c. R; DOWNS: AL V 2,174,186

AIR CONDITIONING APPARATUS Filed May 14, 1935 7 Sheds-Sheet lulu INVENTORS CHARLES 2.00X/V/V6 Patented Sept. 26, I939 UNlTED srATEs PATENT OFFlCE AIR CONDITIONING APPARATUS Charles R. Downs, Greenwich, Conn, and Joseph W. Spisclman, Brooklyn, N. Y., assignors, by mesne assignments, to The Calorider Corporation, Old Greenwich, Coma, a corporation of Connecticut Application May 14, 1935, Serial No. 21,326

11 Claims. (Cl. 183-4) This invention relates to an air or gas conditime, d e t the ad ition 01 ye air and the timing apparatus and operating control therefor. mixing oi. this dry air with, the humidified air, The object of the invention is to provide an air the conditioned air is discharged into the enclosed and gas conditioning apparatus and method of Sp p ly a temperature pp xi in 5 operating the same which will have ahlgh opthat at which the enclosed space is to be main- 5 crating emciency, with a low original cost and low m d at a um d ty which is w y below operating costs, and to provide automatically opthe saturation point and condensation oi moisture crating means for controlling the operation and in the ducts or adj e t Outlets is vo i'or maintaining the apparatus in service. The Furthermore, the relative humidity of the air dispresent apparatus embodies several improvecharged into the enclosed space is suillciently low ments on that disclosed in the copending applicato lessen the likelihood of moisture condensing on t on of Charles R. Downs, Serial No. 672,415, filed cold windows and walls in the vicinity of the air May 23, 1933, now Patent No. 2,026,936, granted discharge ns i t the enclosed p January 6, 1936. i Another object oi. the invention is to provide .One oi! the objects of the invention is to provide an air conditioning apparatus capable of de- 15 an apparatus or the type disclosed in the above humidifying the air within an enclosed space mentioned application in which air may be deend which d s fo s de d y effect humidified, for conditioning air within an enp n he ex n of m i re nd h be w n closed space with or without cooling said enclosed the air and deliqueseent Substance, u as space during hot summer weather and which may calcium chloride, and a series-oi cooling coils and 20 be converted for use in humidliyin air in the to p vid m ns w e y t t p tur f th enclosed space with or without heating said enconditioned air leaving the apparatus is controlled closed space by the apparatus during cold winter y m ically rendering the cooling 001 5 P- months. In carrying out this object, the app erative when the discharge air temperature exratus is so designed that the required changes oeeds a certain maximum and causing he oolin 25 from summer to winter operation or vice versa, co to be again rendered inoperative W e i may be accomplished in a very short tun and temperature of the said conditioned air ialls bewithout structural changes in the equipment. low a certain predetermined m Another object of theinvention is to provide an Another object of the invention 18 t pr vi e ai nditionin apparatus whi h, f r d h ldlan apparatus which in hot weather operates to 30 flcation purposes, depends upon a solid deliquesdehumidify 1111 Within an enclosed p means cent material for its drying efiect and which is being Provided for renderini the entire pp u provided with a liquid phase drying zone and a inoperative when the air within the enclosed space solid phase drying zone, means being provided is reduced t a p e te ed degree of humidity whereby air to be conditioned obtained from witha d to automatically s a the apparatus when a in or without the enclosed space, may be passed the humidity wi the enolosed'spaoe rises above in series through these zones and then disa p ed ed degree- Slmllerly, an Object of charged to the space to be conditioned, and means the i v nt is't pr v d a p a atus which in also being provided whereby these zones, upon cold weather operates to humidity air within an 40 conversion of the apparatus for winter use, are enclosed sp means being Provided whereby the changed into a liquid phase humldiiying zone entire apparatus is rendered inoperative when followed by an air heating zone whereby humidithe humidity of the a Within the enclosed Space fled air below its saturation point may be disreaches a predetermined ma mum and to autocharged into the space to be conditioned. ally start the apparatus n intain it In the use of the apparatus for humidiflcation. n Operation When the humidity falls l w a 45 provision may be made for passing air from withprede ed ree o relative humidityin the enclosed space directly into both zones in Another object of the invention is to P v series parallel relation and for subsequent mixing an air conditioning apparatus which employs a of the humidified air with dry or untreated air solution of calcium chloride for drying effect and in the heating zone. Thus in summer use, the which employs a pumping system for circulation 60 passing of the air in series through the drying of such solution and which is provided with zones effects maximum drying of the air to be m s wh y t is u p sys may e t mconditioned, while in winter use the. series parallel porarily used for pumping the solution to a storpassage of air through the converted zones effects age or to a discharge point, or for bringing the humidiilcation and heating, while at the same same from storage into the apparatus, and also 66 for circulating heated water in the apparatus in the absence of a drying medium when the apparatus is employed for humidiflcation purposes.

Another object oi the invention is to provide an apparatus which is designed to humidity air by the withdrawal of water from a reservoir, heating the water and contacting it with the air, means being provided for regulating and removing to waste a small portion of the water from the reservoir while simultaneously replenishing the same to keep down deposition of salt in the apparatus and facilitate heat transfer therein.

Another object oi the invention is to provide a dehumidifying method and apparatus wherein congelation of concentrated deliquescent solution within or dripping from abed of solid deliquescent material through which air is passed for the purpose of dehumidiflcation, is prevented so that the apparatus does not become clogged from congelation of the solution of the deliquescent material.

Another object of the invention is to provide an air conditioning apparatus including a liquid phase drying zone in which there is contained a liquid drying agent and a solid phase drying zone in which there is contained a bed of a solid drying agent through which zones air is passed in series in the order named, means being provided in the liquid phase zone for causing the air passing therethrough to entrain particles of the liquid drying agent, and means also being provided for preventing the air from carrying such entrained particles into the solid phase drying zone to prematurely liquefy the solid drying agent.

Various other objects and advantages of the invention will be apparent as the embodiments thereof are described more in detail.

In the form of embodiment of the invention herein illustrated:

Figure l is a vertical longitudinal section of the air conditioning apparatus proper comprising the present invention,

Figure '2 is a horizontal sectional view' taken substantially along the line 22 of Figure 1,

Figure 3 is a horizontal sectional view taken substantially along the line 3-3 of Figure 1,

Figure 4 is a vertical transverse sectional view taken substantially along the line 4-4 of Figure 1,

Figure 5 is a vertical transverse sectional view taken substantially along the line 5-5 of Figure 1,

Figure 6 is a horizontal sectional view taken substantially along the line 6-4 of Figure 1,

Figure 'l is a vertical transverse sectional view taken substantially along the line of Figure 1,

Figure 8 is a vertical transverse sectional view conditioning apparatus together with its auxiliary equipment and controls,

Figure 12 is a diagrammatic view showing one formofelectricalwiringandcontrolsystememployed inv connection with the present invention, and

Figure 13 is an end view of a liquid holding tray :mployed in connection with the present invenion.

The air conditioning unit shown for the purposes of illustrating our invention comprises a rectangular casing l0 having side walls I! and I4, end walls l8 and It, a bottom 30, and a cover or top 22 which is hinged to the casing iii. The side walls I! and i4 and the end walls I 6 and I8 are preferably formed of sheet metal and suitably galvanized or otherwise protected from corrosion. Sheets of heat'insulating or decorative material 24 may be used to encase the casing'lll.

Extending longitudinally through the chamber provided by the rectangular casing I0, and occupying a horizontal position in this chamber, is a partition 23 which is formed of several independent removable sections the function of which will be hereinafter described. This partition 28 divides the chamber into a solid phase drying compartment above, and a liquid phase drying compartment below, which compartments provide what are hereinafter referred to as a solid phase drying zone and a liquid phase drying zone respectively. Air to be conditioned is passed first through the liquid phase drying zone where it gives up a portion of its moisture, and subsequently through the solid phase drying zone where the remaining moisture is extracted therefrom.

The air mters the casing l0 through an inlet duct 32 leading from an air chute 33 and leaves the casing through an outlet duct 34 in the solid phase drying zone communicating with the discharge ducts 9 I. A blower or fan 36 serves to circulate the air through the conditioning unit Ill and the space to be conditioned.

In Figure 11, the air chute 33 is shown as communicating with an air conduit 35 which in turn communicates with the interior of the enclosed space, in this instance the first and other floors of the particular dwelling house or building in which the conditioning apparatus is installed, to withdraw air therefrom and the discharge ducts 9| communicate with the same spaces or floors to discharge conditioned airtherein, the outlet and inlet oi the ducts 9i and 35 being suitably spaced to secure circulation of the conditioned air through said spaces. In order to reduce vibration and to keep noises at aminimum, the air chute 33, and conduit 35 may be lined with a sound deadening material 31.

The solid phase drying zone 28 is provided with a series of compartments 38, 40 and 42, for receiving solid calcium chloride or other deliquescent material, preferably in the form of lumps or briquettes which are fed to the compartments from respective hoppers 44, 46 and 48. Air passing through the calcium chloride material gives up a portion of its moisture which causes liquefaction of the material so that the fragments of the material are reduced in size and as the lumps in the compartments 38, 40 and 42 settle, new material is automatically fed down from the hoppers 44, 46 and 48. The solid calcium chloride in the first compartment 38 is liquefied more rapidly than in the second compartment 40 and last compartment 42, so that the hoppers 44, 48 and 48 are proportioned so as to provide adequate supply to the respective compartments at approximately the rate it is used, so that the charge in the hoppers 44, 46 and 43 lasts about the same length of time.

The partially dehumidifled air from the liquid phase zone enters the solid phase zone near the wall it of the casing II and passes through a screen 48 which supports the leading face of the mass of solid calcium chloride contained in the first compartment 88. Moisture in the air issuing from the liquid phase drying zone is absorbed by the lumps in the compartment 88 and additional moisture is removed from the air in its passage through this compartment. Interposed between the compartments 88 and 48 is a heat exchanger unit 41 having screens 48 and 58 on opposite sides thereof to keep the solid calcium chloride contained in these compartments from coming into direct contact with the same and to prevent liquefied material from flowing into the openings in the heat exchanger and congealing therein. A second heat exchanger unit 52 is interposed between the compartments 48 and 42 and this unit is similarly protected by screens 54 and 56 on opposite sides thereof. A screen 58 supports the solid calcium chloride in the compartment 42 to prevent the same from passing into the outlet duct 34 and removable screens 62 support the calcium chloride lumps at the bottom of thecompartments 88, 48 and 42.

Air from the compartment 88 passes successively through the heat exchanger unit 41, the solid material in the compartment 48, the heat exchanger unit 52, the solid material in the compartment 42, the screen 58, and leaves the solid phase zone through the outlet duct 34.

The heat exchangers are preferably formed of finned tubing through which water, chilled brine or other cooling liquid or fluid is circulated while the air passing through the apparatus from one compartment to' another comes in contact therewith to remove theheat due to condensation of moisture removed from the air, together with the heat of solution of the calcium chloride that has been liquefied. It has been our experience that dehumidification of the air without actual refrigeration or reduction of its initial temperature is generally all that is necessary to provide comfort and that dry air is more satisfactory than refrigerated air for normal summer conditions; therefore we prefer to use the heat exchange units 41 and 52 only to prevent increase in the temperature of the air and to remove the heat generated in the calcium chloride beds as the moisture is removed. For this purpose ordinary tap water or city water is usually sufficient. If desired, it is of course possible to circulate artificially cooled water or brine or the like, through the coils of the heat exchangers 52 and 41 to further reduce the temperature. By the provision of the heat exchangers 52 and 41, the average temperature of any one bed may be maintained at a progressively lower temperature than that of the preceding bed.

The partition 26 is sectional in form and com-.

prises a plurality of angle pieces 68 which are secured to the lower edge of the screens, 48, 58, 54, 56 and 58. Removable screen bottoms 62 are received between the angle pieces 68 so as to rest loosely thereon and each screen its coextensive with the bottom of one of the compartments 88, 48 or 42 and comprises the sole support for the calcium chloride contained therein. In this way the drainage of the liquefied calcium chloride from the compartments 88, 48 and 42 is not interfered with and clogging of the apparatus due to congelation of the liquefied material is prevented.

The liquid phase drying zone 88 below the solid phase drying zone 28 is provided with a series of horizontal staggered trays 14 which are arranged in cascade relationship, so that a solusuch a manner as to form substantially liquid and air tight joints and the free edges of the trays are provided with lips 16. In this manner a shallow pool of liquid is maintained on each tray while the overflow descends from tray to tray. The trays 14 are spaced apart by spacers 14a and are held together by the bolts 16a.

The uppermost tray 14 is slightly spaced from the partition 28 and extends forwardly of the partition 26 a slight distance at the forward end thereof. A plurality of baffles 64, 86 and B8 depend from the partition 26 topoints slightly spaced from the upper tray 14 and, by dipping into the solution carried by this tray, provide a liquid seal for preventing air issuing from the liquid phase drying zone 88 from by-passing the solid phase zone or any portion thereof on its way to the outlet duct 84. A solid plate 18 connects the bottom of the screen 58 with the wall I8. At the bottom of the zone 38 there is provided a reservoir 18 having a serpentine coil cooling unit 88 (shown in Figures land 3) disposed therein. This cooling unit is in the form of a tortuous conduit having a water inlet 82 at one side of the reservoir 18 and a water outlet 84 at the other side thereof. The unit 88 is immersed in the solution of calcium chloride which collects in the reservoir 18 after passing over the trays 14. A partition 86 in the form of a tray extends over the reservoir I8 and is spaced from the endwall thereof. The rear edge of this partition 86 is provided with a lip 89 to prevent overflow of solution at this edge. The end of the partition 85 with the lip 89 extends forwardly in the apparatus a distance slightly greater than the extent of the tray 14 immediately above, thus permitting the cascade issuing from this tray to be received on the partition 86. The opposite end of partition 86 is provided with an opening 8| (see Figures 1 and 3). at one side thereof, through which the calcium chloride solution flows into the reservoir 18. A plurality of staggered baffles 83' (Figure 3) extend longitudinally of the reservoir 18 between the passes of the tortuous cooling unit 88. The opening 81 permits the calciumfchloride A to enter the reservoir 18 at one extreme side of the apparatus where it is obligedtofl flow along the tortuous path provided bythe ".bailiejs 88' to a point of discharge at the other side of the same and thereby fiow counter-current to the cooling water or other liquid which enters the serpentine coil 88 at 82. An overflow outlet 88 (Figures .1, 3

and 6) is provided for the reservoir 18above the level of the immersed cooling unit88. This outlet is so positioned that the immersed cooling unit 88 is completely submerged in the calcium chloface of the liquid phase drying zone is thusmaterially increased in area which is conductive toward greater moisture absorption in this zone. To prevent droplets of the calcium chloride solution being carried by the air into the first compartment 38 of the solid phase drying zone 28 and causing premature liquefaction of the solid cal-.-

cium chloride in the first compartment, the eascade issuing from the uppermost tray ll, is divided by a liplI' (Figures 2, 6 and 13) provided on the tbp tray II, which lip divides the cascade issuing from this tray and provides a comparatively large opening through the cascade centrally thereof through which the air may pass unobstructed. During its passage from the cascade issuing from the tray I4 immediately below the uppermost tray to the screen 4!, the entrained particles of calcium chloride solution contained in the air have an opportiunity to settle out so that when the air reaches the screen 45 it is substantially free from droplets of calcium chloride solution.

The air stream passing beneath the uppermost tray I4 is prevented from passing between this tray and the bottom of the solid phase drying zone by virtue of the baffles l4, 88, 8t and plate Iii, and enters the solid phase drying zone, passing through the compartments 3!, 40 and 42 to be further 'dehumidifled in the manner outlined above. The arrangement of the upper tray I4 and baiiies ll, 06, 68 and plate ill is such that there will be free and unobstructed drainage of the material liquefied in the.solid phase drying zone compartments 3|. Ill and 42 through the screen bottoms S2. The concentrated calcium chloride solution which drains through these screens 62 drips into a comparatively dilute solution of calcium chloride circulated over the uppermost tray II and thus resolidiflcation of the concentrated solution on the upper tray 14 is prevented. At the same time the uppermost tray 14 prevents the air from circulating along the bottom of the beds I8, 40 and I1 and chilling or causing congelation of the liquefied calcium chloride which forms in the beds and drips onto the 'toptray I4.

I The screen openings of the screens "must be large enough to permit the flow of the viscous solution therethrough, but we prefer to use open- -ings,larger than such minimum so as to permit even solid particles of calcium chloride in the bottom of the compartments 18, 40 and 42, which have been reduced to small size by the liquefaction,to pass through the screens and onto the uppermost tray H. For example, if the screen openings are V inch to y, inch in diameter provision is made for adequate solution drainage-and furthermore, whenever particles of the solid deliquescent material which originally are preferably from 1 to 2 inches in diameter are reduced in size so that they will fall through these openings under the conditions prevailing in the bed, they are automatically removed from the bed and fall onto the uppermost tray ll. In this position,

they are swept by the recirculating dilute solusaturated air issuing from the humidifying nonev and/or mixing with air which is withdrawn from the enclosed space. Accordingly. ,the masses of calcium chloride remaining in the machine are taken out of the compartments 38,4 and 4.2 in

the solid phase drying zone and all of the calcium chloride solution in the liquid .phase drying zone, including the liquid on the trays 14 (which are provided with small drainage holes for the purpose), the partition 86, and the reservoir 18, is removed. The apparatus is then ready for humidifying air by circulating heated water over the trays l4 and the partition N. The heat exchanging units 41 and 52 may be used toheat the air which has been humidified by circulation over the hot water on the trays H so as to reduce its relative humidity to a point at which condensation of water in the ducts or at the outlets is avoided. The units 52 and 41 are preferably used in series with the water circulated over the trays l4, and the water in this circuit heated by means of an external heater 218 (Figure 11) of the ordinary household type. It is also possible to heat the water which is applied to the trays H by such a heater and have the heat exchanging units 52 and 41 remain inoperative.

In winter use air is introduced into the lower compartment or humidifying .zone through the inlet 32, and being drawn by the action of the blower 38, flows above and below the partition 86 and follows the tortuous path provided for it by the staggered trays H. The air in thus crossing the cascades and in being exposed to large surfaces of heated water, absorbs moisture and enters the heating or mixing zone 28 in a nearly saturated condition.

A short conduit section 94 having a damper 98 therein, extends from the air chute I3 and communicates with the mixing or heating zone. Air may be introduced through this conduit and mingled with the nearly saturated air issuing from the humidifying zone and the mixed air is passed through the heat exchangers l1 and I2 and discharged from the apparatus through the outlet 34, or, if desired, the damper 96 may be. left closed and the humidified air only heated by passage through the heat exchangers 41 and 62. The heating or mixing reduces the relative humidity of the air issuing from the apparatus to a point considerably below the saturation point and. thus prevents condensation. Provision is made whereby heated water may be passed, first through theheating unit 52 and subsequently through the unit 41, to be discharged on the uppermost tray 14 at a reduced temperature, from whence it flows downwardly in cascade fashion into the reservoir 18 for recirculation through the heating unit and back to the heat exchanging units 5! and 41. By passing the heated water through the heat exchanging units first, the air is heated after it has been humidified thereby reducing its relative humidity which under certain conditions permts the closing of damper 88 and eliminates the introduction of unhumidified air at this point. In this method of effecting humidity and heating, the submerged heat exchange unit It is not used.

The operating devices and connections such as conduits, valves, pumps, motors, and other instrumentalities for causing the apparatus to function both for winter and summer use, are enclosed within a casing N which is secured to the casing II. The casing 85 is provided with a door '8 through which access may be had to I these parts. The blower I. is supported within this casing and draws conditioned air from the casing i0 and discharges it into an outlet sound sound absorbing material or employ suitable absorption chamber 81 which may be lined with baffles for this purpose. This sound absorption chamber may be provided with one or more outlets 89 which are connected by conduit sections 8| tothe various rooms or parts of the enclosed space to be conditioned.

Referring now to Figures 1, 3, 6 and 7, a pump is designated at I00. Means is provided whereby this pump may be utilized to circulate the calcium chloride solution in the reservoir 18 over the trays 14, and toward this end, the intake or pump inlet I02 is connected by means of conduit sections I04, I06 and I to the interior of the reservoir 18 at a point below the bottom thereof by an elbow fitting H0.

The discharge or pump outlet H2 is connected by means of conduit sections H4, H6 to a three way valve II8 which normally directs the solution being pumped to the top tray M of the liquid phase drying zone 30 through conduit sections I20, I22 which latter section passes through the wall of the casing I0 into the interior oi the same and terminatessin a header nozzle I24 above the uppermost tray 14. The solution discharged upon the upper tray 14 receives the concentrated calcium chloride solution and any small lumps of solid calcium chloride dripping from the beds 38, 40 and 42 in the solid phase zone 29 and the resultant solution passes downwardly from tray totray in the manner previously described and returns to the reservoir 18 for recirculation.

In order to cool the calcium chloride solution in the reservoir 10, means is provided for circulating cold water or other cooling medium from a source of supply, as for example, the city water main, cold well or the like, through the immersed cooling unit 80. In some installations 'where a greater cooling is desired, artificially cooled water, brine or other cooling fluids may be circulated through the immersed cooling unit 80. For example, cold water is conducted from a source of water supply (not shown) through conduit section I26, solenoid valve I20 (Figure 10), conduit section I30, gate valve I32 and conduit section I34 to the inlet 82 of the immersed cooling unit 80 in the reservoir 18. Water thus introduced into the immersed radiator 80 is circulated through the tortuous path provided by the tubes thereof to the outlet 84.

The cooling medium entering the submerged cooling unit 80 travels through the tortuous paths of this radiator in a direction opposed to the flow of calcium chloride solution following the tortuous path 93 betweenthe baiiles 93' in the reservoir 18. The calcium chloride solution is therefore progressively cooled as it travels toward the outlet provided by the elbow fitting H0.

The heat exchange units or coolers 41 and 52, contained within the solid phase drying zone as, are connected in series with each other and with the immersed cooling unit 80. Cooling water issuing from the outlet 84 of the immersed cooling unit 80 is carried upwardly through a vertical riser I86 (Figures 1 and 8), conduit sections I38, and enters the cooling unit 52 through an inlet I39 in the bottom thereof. The water or other cooling fluid is circulated through this unit and emerges from the outlet I40 at the top thereof from whence it is carried through the conduit I42 to the inlet I46 of the cooling unit 41. The water or other cooling medium latter being circulated through the cooling unit 41, passes through the outlet I48 thereof, through the conduit I50 (see Figures 1 and 7) to a three way valve I58 (Figure 6) (which has a winter use) and through a conduit I52 from whence it may be discharged to the sewer or the water may be used for other purposes since it is not contaminated in any way.

The cooling units 80, 41 and 52 have been shown and described as being connected in series. They may however, be connected -in parallel when desired.

In order to discharge the excess calcium chloride solution which collects in the reservoir 18, a small capacity pump 220 (Figures 3, 6 and 7) has its inlet 222 connected through conduit sections 224, 226, to the overflow 90 from the reservoir 18. The excess solution is thus carried through the pump 220 to the outlet 22? thereof and discharged through a pipe line 229 (Figure 11) to the top of a storage tank 229 through an enlarged header 230 having a sight glass MI and a valve 231 therein. A conduit 239 communicates with the header 233 above the valve 231 and this conduit communicates with the sewer or other point oi discharge for waste material. By closing the valve 231, all of the calcium chloride solution issuing from the reservoir may be discharged to waste and by leaving the valve 221 open, the storage tank 229 is permitted to receive the solution until its capacity has been reached when the solution will automatically flow to waste through the conduit 239.,

The solenoid or other remote control valve I28 (Figures 6, '7, 8 and in the line I26, I00, I34 leading from the source of cold water supply to the immersed cooling unit 00 is automatically operated to permit circulation of cooling water through the cooling units 80, 52 and 41 or to prevent such circulation, depending upon the temperature of the conditioned air leaving the appa ratus. A thermostat I80 (Figures 11 and 12), having terminals I8I and I83 is located in the outlet chamber 81. The terminal IOI is electrically connected by a lead a to one terminal I86 of the solenoid valve I20. The other terminal I03 of the thermostat I00 is connected by a lead I) to a relay.238. A lead 0 connects the other terminal I88 of the solenoid valve I28 to the relay. The relay 238 is designed to supply electrical current through lead I), thermostat I80, lead a, solenoid valve I28 and back through lead 0, in such a manner that, when a predetermined temperature is reached in the outlet chamber 81, the thermostat I80 closes the circuit just described so that the solenoid valve opens to permit cooling water to pass through the same. Conversely, when the temperature in the outlet chamber 81 drops below a predetermined degree, the solenoid valve is permitted to close and prevent the passage of cooling water therethrough until the temperature of the discharged air again rises to a point where cooling is desirable.

One form of solenoid valve I28 which may be used is shown in detail in Figure 10, although any suitable electrically or temperature controlled valve may be used. In the form shown a housing I90 has a valvechamber I92 therein provided with an inlet I94 and an outlet I96. A web 198 extends across the chamber I92 andis provided with a valve seat 200 adapted to normally be closed by a valve 202 carried by a movable core 204 which is slidably mounted within the casing I90. In order to maintain the valve 202 on its seat, a spring 206 serves to normally urge the core and valve downwardly against the seat. Positioned within the housing I 90 and surrounding the core 204 is a magnetic coil 208 which is normaily de-energized but which, when energized, causes the core to be moved upwardly to lift the valve 202 from its-seat to permit cooling water to flow through the housing I80. The upper end of the housing I80 is provided with a threaded opening 2I0 in which there is threadably received a plug 2I2 of insulating material which carries the terminals I88 and I88 for the coil 208. A sheath 2I8 has one end thereof threadably received in the opening 2I0 and the leads a and c extend through the sheath 2 I8 and connect the terminals I88 and I88 with the terminal Ill 01' the thermostat I80 and with the relay 288 respectively.

The pump I and the pump 220 are designed to be driven in unison from the common shaft 280 of an electric motor 282. The blower 88, which draws air through the apparatus, is likewise driven by an electric motor 288 (Figures 1 and 12). When it is desired to reduce the humidity of air within the enclosed space, the motors 282 and 288 are automatically started by the operation of the humidostat 288, and when the humidity reaches a predetermined degree, both pumps I00 and 220 and the blower 88, are automatically caused to cease their operation, while at the same time the thermostatic control of the solenoid valve I28 is over-ridden so that this valve closes, and the entire apparatus remains at a standstill.

The motors 282 and 288 which control the operation of the blower 88 and of the pumps I00 and 220 respectively receive current from the relay 288 through the respective leads d and e and f and g. The humidostat 288 positioned within the enclosed space and operating on a reduced voltage circuit hi from the line :r-u has one terminal I58 connected through a switch 28I to the relay 288 by means 01 the lead i while the other terminal I 58 is connected through the switch 2M to the lead n.

When the humidostat 288 is set for example for a relative humidity of 80 to 82, if the actual bu midity in the enclosed space is above this setting, the contacts 01 the humidostat remain closed, the relay 288 is energized and contact 288a is held against contact 2881) to complete the circuit from the lines :e-y through the motors 282 and 288 and the solenoid valve I28 to cause the motor 282 to operate the blower 88 to draw air through the apparatus, the motor 288 to operate the pump I08 to pump the liquid calcium chloride, and the valve I28 to remain open if the thermostat I80 so provides to permit cooling water or other fluid to cirgulalte through the heat exchange units 80, 82 an When the relative humidity in the enclosed space is reduced below that for which the humidostat 288 is set, the contacts of the humidostat will open, current through the relay 288 will be broken and contact 2880 will separate from contact 2881) to interrupt the current and stop the motors 282 and 288 and permit the valve I28 to close until the humidostat 288 again calls for operation oi the dehumifying apparatus.

In the winter use oi the apparatus for humidii'ying and heating the air, the humidostat 288 is caused to start the operation of the motors 282 and 288 when the humidity falls below the setting of the humidostat and to stop the operation of the motors 282 and 288 and permit the valve I28 to close when the humidity equals or rises above the setting of the humido- Sm m. For this result the switch 2 is caused to connect the leads h and i of the relay circuit to the terminals I58 and I88 of the humidostat 288. The humidostat 288 is set to open its contacts ii the relative humidity exceeds the predetermined setting, ior example 80. The humidostat will then conduct current through the leads h and i only when the humidity in the space undergoing conditioning is below the seting or the humidostat and under this condition the motors 282 and 288 will operate to cause the blower 88 to draw air through the apparatus and I the pump I00 to pump heated water through the heat exchange units 82 and 81 over the trays 18 in the manner previously described. When the humidity in the enclosed space reaches the predetermined relative humidity for which the humidostat 288 is set the contacts of the humidostat are automatically broken which breaks the circuit through the relay 288 and causes the operation of the motors 282, 288, etc., to cease.

Inasmuch as the initial deliquescence of the solid calcium chloride in the compartments 88, 80 and 82 is comparatively slow in starting the apparatus for summer use, it is advisable to flood the trays 18 in the liquid phase zone by pumping some of the solution of calcium chloride from the storage tank 228 to these trays. Accordingly, a conduit 282 (Figures 6 and 11), leading from the storage tank 228 communicates with the suc tion line I08,;I08 oi the pump I00 through a conduit 288 and a three way valve 288. The valve 288 is adjusted to close the conduit I08 leading to the reservoir 18 to permit the calcium chloride to flow from the storage tank 228 through the circuit Just described to the uppermost tray 18 through the conduit sections I20, I22. This fluid circuit is maintained until such time as the reservoir I8 is filled at which time the valve 288 is adjusted to exclude the conduit section 288 from the suction line I08, I88 of the pump I00, and to open the line from the reservoir I8 which leads to the pump I00 through the conduit sect I08, I08 and I08. The reservoir I8, being fllle ,Jthe pump I00 during periods of operation circulates the solution over the trays in the manner previously described.

After the apparatus has been in use as a dehumidifler during the summer and it is desired to cease further operation of the same until the winter season sets in, when the apparatus is to be then converted to use as a humidifier, certain operations are carried out to prepare the apparatus for this purpose.

Any solid calcium chloride material remaining in the compartments 88, 80 and 82 in the solid phase drying zone 28, is removed and subsequently the calcium chloride solution in the reservoir I8 is pumped either to the storage tank 228 or into a tank truck or the like.

Accordingly, a conduit 288, communicating with the conduit sections H8, H8, and leading to one branch of a three way valve .288, communicates through a conduit 280 and a gate valve 282 with an outlet 288 which may discharge into a tank truck. By properly adjusting the valve 288 to exclude the conduit 288 from the suction line of the pump I00, by operating the,

to withdraw calcium chloride solution in the 7d reservoir 18 through the elbow fltting IIO, conduit section I08, valve 288, conduit sections I08 and I08, pump I00, conduit sections H8 and 288, valve 258, conduit section 280, and gate valve 262 to the outlet as leading to said tank truck. 7

In order to conduct the calcium chloride in the reservoir 18 to the. storage tank 229, the three way valve 258 has a branch communicating with a conduit section 266 which in turn communicates with the conduit section 242, leading to the storage tank 229. By leaving the adjustment of the valves 246 and H8 the same as when the calcium chloride is carried to a tank truck, and by adjusting the valve 258 to cause intercommimication between the conduit sections 256 and 266, the pump I66 may be operated to withdraw calcium chloride solution from the reservoir 16 through the conduit section I66, valve 246, conduit sections I66 and I64, pump I66, conduit, sections II4 and-256, valve 258, and conduit sections 266 and 242 to the storage tank 229.

It will be seen therefore that the valve 258 may be operated to divert the solution issuing from the reservoir 16 either to the said tank truck or to the storage tank 229.

In using the apparatus in winter as a humidiher, for the purpose of illustration, it may be assumed that the solid calcium chloride in the compartments 38, 46 and 42, together with the calcium chloride solution in the trays 14, the partition 86, and the reservoir I6 has been removed and that both the solid phase drying zone and the liquid phase drying zone are empty. Itwill be remembered that the solid phase drying zone is converted into a mixing or heating zone and that the liquid phase drying zone is converted into a humidifying zone vfor direct contact of the air with the heated water.

The thermostat I86 is set for-its minimum temperature and therefore the solenoid valve I28 which it controls remains open. Thus in the winter use of the apparatus, the thermostat in effect is rendered inoperative as a control instrument, except as it is over-ridden by the humidostat 236, and the solenoid valve I26 remains open throughout the use of the apparatus as a humidifler.

The leads h and i of the humidostat 236 are reversed upon the terminals I54 and I58 by throwing the polarity reversing switch 24I so that when the relative humidity of air in the enclosed space falls below a predetermined setting, the humidostat 236 closes the circuit through the relay 236 to cause the motors 232 and 234 to operate the pump I66 and the blower 36 and to cause the valve M8 to open. The gate valve I32 is closed and the needle valve 268 is fully opened while at the same time, the valve H6 is adjusted to establish communication between the conduit sections H4, H6 and a conduit section 216 leading to a heater 216. As the apparatus is started, water is then caused to flow from the water main through the conduit section I26, solenoid valve I28, conduit section I36, needle valve 266, conduit sections 261 and I64, pump I66, conduit sections I14 and H6, valve H8, and conduit section 216 to the heater 218. After being heated, the water thus introduced to the heater 218 passesthrough conduit sections 286 and 282, to a T 284 (Figures 1 and 6) disposed in the vertical riser I36, and from thence to the heat exchanger units 52 and 41 in the order named. After leaving the heat exchanger unit 41, the water which has lost a portion of its heat to the air passing through the heating and mixing zone 38, passes through the conduit I56 to the valve I55 and through conduit sections I51 and I22 to the nozzle I24 where it is discharged onto the uppermost tray 14 for humidiflcation of air in the humidifying zone 28 as previously described.

When the water thus admitted to the trays 14 finds its way into the reservoir 18 and this reservoir becomes filled, the needle valve 268 is adjusted so that a limited amount of water, slightly in excess of the deficiency created by evaporation in the humidifying zone 36, is permitted to pass through the conduit section 261 to the intake line I64 oi the pump I66, the excess water serving to carry away salts that may be formed upon evaporation in the apparatus. The valve 246 is then adjusted to establish communication between the conduit sections I68 and I66. The pump then operates to withdraw the water in the reservoir 18 and pump it through the circuit previously described leading from the pump I66 to the heater 218. During the use of the apparatus as a humidifier, the flow of water from the reservoir 18 through the heater 218 and heat exchanging units 52 and 41 to the uppermost tray 14 is continuous.

As an alternative method of effecting humidiflcation, means is provided whereby water may be circulated from the reservoir to the heater 216 and from there directly to the uppermost tray 14, the heat exchanger units 62 and 41 remaining inoperative. Toward this end a three way valve 286 is interposed in the line leading from the heater 218 to the heat exchanger unit 62. Conduit sections 286 and 296 lead from the valve 266 to the valve I55 and thus water may be pumped continuously from the reservoir 16, through conduit sections I68, I66, I64, pump I66, conduit sections II4, II6, valve H6, and conduit section 216 to the heater 216. From the heater, the water is sent to the uppermost tray 14 through conduit section 266, valve 286, conduit sections 288 and 296, valve I55, conduit sect-ions I51 and I22 and nozzle I 24. In winter the overflow pump 226 serves to carry away the excess water added above that required for humidiflcation.

While we have described in considerable detail a,preferred embodiment of our invention it will be readily understood that various modifications and changes may be made therein and equivalents used for various of the parts specifically described, without departing from the principles of our invention or the scope of the appended claims.

We claim:

1. In an air conditioning apparatus having a solid phase drying zone, comprising a plurality of compartments containing solid calcium chloride, heat exchange units separating said compartments, means to circulate air through said compartments to remove moisture therefrom and through said heat exchange units, means to circulate a cooling fluid through said heat exchange units to remove heat from the air, and means controlled by the temperature of the air to start and stop the flow of cooling fluid through said heat exchange units.

, 2. In an air conditioning apparatus having a solid phase drying zone, comprising a plurality of compartments containing solid calcium chloride, heat exchange units separating said compartments, means to circulate air through said compartments to remove moisture therefrom and through said heat exchange units, means to circulate a cooling fluid through said heat exchange units to remove heat from the air, means controlled by the temperature of the discharged air to start and stop the flow of cooling fluid through said heat exchange units, and means controlled by the humidity of the air in the conair through said apparatus.

3. In an air conditioning apparatus, a solid phase drying zone comprising a plurality of longltudinally spaced compartments containing solid calcium chloride, said compartments having perforate bottoms occupying'substantially the same horizontal plane, means for passing air to be dehumidifled successively. through said compartments, cooling units disposed between acLiacent compartments for removing the latent heat of condensation of moisture removed from the air together with the heat of solution of the calcium chloride, a pool of calcium chloride solution extending underneath said bottoms and being subs stantially coextensive therewith and into which calcium chloride solution resulting from the deliquescence of solid material in said compartments is adapted to drain, and bames extending downwardly from each cooling unit into said pool, and a baflie extending downwardly from the forward edge of the first longitudinal compartment into said pool, said battles serving to exclude the passage of air between said pool and the bottoms of said compartments.

'4. An air conditioning apparatus comprising in combination a casing containing a solid phase drying zone and a liquid phase dryingzone, said solid phase drying zone comprising a plurality of adjacent compartments containingsolid calcium chloride, said compartments having periorate bottoms, said liquid phase drying zone comprising a plurality of superimposed staggered trays beneath said compartments, the uppermost tray being substantially coextensive with the bottoms of said compartments and being adapted to receive thereon a pool of calcium chloride resulting from the deliquescence of solid material in said compartments, said uppermost tray being adapted to overflow said solution onto the next adjacent tray and from said latter tray downwardly from tray to tray in cascade fashion, means for admitting air into said casing below said trays, means for drawing the air upwardly over the surfaces of said trays into the solid phase drying zone and successively through said compartments, means for collecting the calcium chloride solution issuing from the lowermost tray and for recirculating the same over said trays, and means for excluding air from passing over the surface of said pool on the uppermost tray whereby air is forced to pass successively through said compartments.

5. In an air conditioning apparatus a plurality of horizontally spaced compartments containing calcium chloride in lump form, means for passing air successively through said compartments for the purpose of dehumidiflcation thereof, cooling unitsinterposed between adjacent compartments and adapted to cool the air passing from one compartment to the next, a screen supporting the leading face of calcium chloride in the first compartment, a screen on each side of each cooling unit for supporting the adjacent faces of calcium chloride in the compartments and for preventing contact of the calcium chloride with said cooling units, and a screen for supporting the rear face of calcium chloride in the last compartment, said compartments having removable screen bottoms with openings which permit the concentrated calcium chloride solution and small particles of calcium chloride produced by deliquescence of said lumps to drop from said compartments.

6. The combination with an air conditioning apparatus having a solid phase dryingzoneadapted to contain solid calcium chloride, of a liquid phase drying zone comprising a series of superimposed trays, the uppermost tray being adapted to receive thereon a solution of calcium chloride resulting from the deliquescence of the solid calcium chloride in said solid phase drying zone, each of the remaining trays being adapted to receive the solution thereon successively by overflow of the solution from the tray above, a reservoir beneath said trays, a partition above said reservoir and below said trays, said partition being in the form of a tray adapted to receive the solution issuing from said trays thereon, there being an opening through said partition adjacent one edge thereof through which the solution thereon flows into said reservoir at one side thereof, means for withdrawing the solution from said reservoir at the other side thereof whereby the same is caused to flow across said reservoir,

means for conducting the withdrawn solution to a liquid phase drying zone wherein the air is contacted with a solution of moisture absorbing material, a reservoir containing a solution of said material, means for conducting air over and in contact with thesurface of the solution in said reservoir, means for introducing the solution to said reservoir atone end thereof, means for withdrawing the solution from the reservoir at the other end thereof, a plurality of staggered bailies extending across said reservoir for causing the liquid to flow in a tortuous path across the reservoir, a cooling unit submerged in said reservoir and comprising a continuous tubular conduit following the tortuous path provided by said baffles, and means for passing a cooling medium through said unit in 'a direction opposed to the direction of flow of said liquid.

8. The combination with an air conditioning apparatus having a solid,phase drying zone including a plurality of beds for solid calcium chloride, a liquid phase drying zone including aplurallty of trays for supporting pools of liquid calcium chloride solution, means for directing air to be dehumidified successively over the surfaces of said pools and then successively through solid calcium chloride in said beds, and a reservoir adapted to receive calcium chloride solution draining from said trays, said reservoir having an overflow outlet, of a storage tank for calcium chloride solution, a pump having a relatively large capacity, and having a fluid inlet and a fluid outlet, a conduit communicating with the bottom of said reservoir and with the inlet of said pump, a second conduit communicating with the outlet of said pump and having a discharge opening for discharging calcium chloride solution onto said trays, a second pump having a relatively small capacity and having a fluid inlet and a fluid outlet, a conduit communicating with said overflow outlet and with the fluid inlet of said last mentioned pump, and a conduit leading from said last mentioned fluid outlet to said storage tank.

9. The combination with an air conditioning apparatus having a mixing zone, a humidifying zone including a plurality of trays for supporting pools of water, means for directing air to be humidified successively over the surfaces of said pools and into said mixing zone, means for introducing air into said mixing zone for admixture with the air issuing from said humidifying zone, and a reservoir for receiving water issuing from said trays, of a pump having an inlet and an outlet, a conduit leading from a source of water supply to said pump inlet, a needle valve in said conduit, a water heater having an inlet and an outlet, a conduit leading from said pump outlet to the inlet of said water heater, a conduit leading from the outlet of said heater to said humidifying zone for supplying water to said trays, and a by-pass conduit having a valve therein for connecting said last two mentioned conduits and excluding said heater.

10. A combination with an air conditioning apparatus having a solid phase drying zone, a liquid phase drying zone, means for directing air to be dehumidified successively through said zones, a reservoir adapted to receive hydroscopic solution draining from said liquid phase drying zone-said reservoir having an overflow outlet, of a storage tank for hygroscopic solution, a pump having a relatively large capacity, and having a fluid inlet and a fluid outlet, a conduit communicating with the bottom of said reservoir and with the' inlet of said pump, a second conduit communicatlng with the outlet of said pump and having a discharge opening for discharging hygroscopic solution into said liquid phase drying zone, a second pump having a relatively small capacity and having a fluid inlet and a fluid outlet, a conduit communicating with said overflow outlet and with the fluid inlet of said last mentioned pump, and a conduit leading from said last mentioned fluid outlet to said storage tank.

11. In an air conditioning apparatus a plurality of horizontally spaced compartments containing calcium chloride in lump form, means for passing air successively through said compartments for the purpose of dehumidiflcation thereof, cooling units interposed between adjacent compartments and adapted to cool the air passing from one compartment to the next, a screen supporting the leading face of calcium chloride in the first compartment, and a screen for supporting the rear face of calcium chloride in the last compartment, said compartments having removable screen bottoms with openings which permit the concentrated calcium chloride solution and small particles of calcium chloride produced by deliquescence of said lumps to drop from said compartments.

CHARLES R. DOWNS. JOSEPH W. SPISELMAN. 

